tam·​per | \ ˈtam-pər How to pronounce tamper (audio) \
tampered; tampering\ ˈtam-​p(ə-​)riŋ How to pronounce tampering (audio) \; tampers

Definition of tamper

 (Entry 1 of 2)

intransitive verb

1a : to interfere so as to weaken or change for the worse used with withdid not want to tamper with tradition
b : to try foolish or dangerous experiments used with with
c : to render something harmful or dangerous by altering its structure or composition was charged with tampering with consumer products
2a : to carry on underhand or improper negotiations (as by bribery)
b : to inflict physical harm, threats, intimidation, or corrupt persuasion with the goal of influencing or preventing a witness's testimony : to engage in witness tampering used with withThese alleged efforts were the basis for Mueller's accusation that Manafort was tampering with a witness, attempting to coach testimony, which would have violated the terms of his bail.— Franklin Foer


tamp·​er | \ ˈtam-pər How to pronounce tamper (audio) \
plural tampers

Definition of tamper (Entry 2 of 2)

: a tool for tamping : tamp entry 2 Using a tamper, tamp the coffee down into the filter …— Lexa Roséan After each truckload of earth fell onto the cobblestones of the Piazza's perimeter, a steamroller flattened it, and five relaxed-looking workmen … patted it smooth with shovels and wooden tampers, and hosed it down.— Lis Harris

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Other Words from tamper


tamperer \ ˈtam-​pər-​ər How to pronounce tamperer (audio) \ noun, plural tamperers
tamperproof \ ˈtam-​pər-​ˌprüf How to pronounce tamperproof (audio) \ adjective

Examples of tamper in a Sentence

Recent Examples on the Web: Verb The document was released shortly after Fotis’s Sept. 4 arrest, when he was charged with tampering with or fabricating physical evidence in connection with the case. Kc Baker, PEOPLE.com, "Husband of Missing Conn. Woman Pleads Not Guilty to Tampering as Judge Issues Gag Order," 12 Sep. 2019 Torres is also charged with tampering with evidence. Hannah Dellinger, Houston Chronicle, "Judge sets bail in tampering case involving death of 5-year-old girl left in closet," 9 Sep. 2019 Dulos and Troconis, were first charged in early June with tampering with evidence and hindering prosecution. Nicholas Rondinone, courant.com, "Police revealed new theories and evidence after Fotis Dulos and Michelle Troconis were arrested for a second time in connection with the Jennifer Farber Dulos case. Here’s what we learned.," 6 Sep. 2019 The 27-year-old Torres was also charged earlier this week with tampering with evidence related to a human corpse. Fox News, "Boyfriend of mother to be charged after body of Texas girl, 5, found in closet," 6 Sep. 2019 Connecticut State police arrested Fotis Dulos at his Farmington home Wednesday afternoon and charged him anew with tampering with physical evidence. CBS News, "Missing mom's body was in truck used by estranged husband, his girlfriend told police," 5 Sep. 2019 Fotis Dulos was charged with tampering with or fabricating physical evidence. Cnn.com Wire Service, The Mercury News, "Jennifer Dulos disappearance: New arrest after DNA found on discarded car seats," 5 Sep. 2019 Based on evidence gathered by Castle Hills police, Wenger had been charged with tampering with evidence and fraudulent possession of identification information, allegedly taken from City Manager Ryan Rapelye’s personnel file. Scott Huddleston, ExpressNews.com, "Castle Hills council drama far from over as power struggle continues in San Antonio suburb," 28 Aug. 2019 Goines was charged with two counts of murder, while his former partner Steven Bryant was charged with tampering with a government record, Harris County prosecutors said. NBC News, "Ex-Houston police officer charged with murder after deadly drug raid," 23 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tamper.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of tamper


1567, in the meaning defined at sense 2


circa 1864, in the meaning defined above

History and Etymology for tamper


probably from Middle French temprer to temper, mix, meddle — more at temper entry 2

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Statistics for tamper

Last Updated

6 Nov 2019

Time Traveler for tamper

The first known use of tamper was in 1567

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More Definitions for tamper


tam·​per | \ ˈtam-pər How to pronounce tamper (audio) \
tampered; tampering

Kids Definition of tamper

: to interfere or change in a secret or incorrect way Someone was tampering with the official records.

Legal Definition of tamper

1 : to bring improper influence to bear (as by bribery or intimidation) used with with tampered with the jurors
2 : to alter or interfere in an unauthorized or improper manner used with with tampered with evidence

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More from Merriam-Webster on tamper

Spanish Central: Translation of tamper

Nglish: Translation of tamper for Spanish Speakers

Britannica.com: Encyclopedia article about tamper

Comments on tamper

What made you want to look up tamper? Please tell us where you read or heard it (including the quote, if possible).


concealed or difficult to comprehend

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